cgroup: fix idr_preload usage

It does not make much sense to call idr_preload with the same gfp mask
as the following idr_alloc, but this is what we do in cgroup_idr_alloc.
This patch fixes the idr_preload usage by making cgroup_idr_alloc call
idr_alloc w/o __GFP_WAIT. Since it is now safe to call cgroup_idr_alloc
with GFP_KERNEL, the patch also fixes all its callers appropriately.

Signed-off-by: Vladimir Davydov <vdavydov@parallels.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
This commit is contained in:
Vladimir Davydov 2015-08-03 15:32:26 +03:00 committed by Tejun Heo
parent 917d8e2d10
commit cf780b7dc7

View File

@ -210,7 +210,7 @@ static int cgroup_idr_alloc(struct idr *idr, void *ptr, int start, int end,
idr_preload(gfp_mask);
spin_lock_bh(&cgroup_idr_lock);
ret = idr_alloc(idr, ptr, start, end, gfp_mask);
ret = idr_alloc(idr, ptr, start, end, gfp_mask & ~__GFP_WAIT);
spin_unlock_bh(&cgroup_idr_lock);
idr_preload_end();
return ret;
@ -1669,7 +1669,7 @@ static int cgroup_setup_root(struct cgroup_root *root, unsigned long ss_mask)
lockdep_assert_held(&cgroup_mutex);
ret = cgroup_idr_alloc(&root->cgroup_idr, root_cgrp, 1, 2, GFP_NOWAIT);
ret = cgroup_idr_alloc(&root->cgroup_idr, root_cgrp, 1, 2, GFP_KERNEL);
if (ret < 0)
goto out;
root_cgrp->id = ret;
@ -4582,7 +4582,7 @@ static int create_css(struct cgroup *cgrp, struct cgroup_subsys *ss,
if (err)
goto err_free_css;
err = cgroup_idr_alloc(&ss->css_idr, NULL, 2, 0, GFP_NOWAIT);
err = cgroup_idr_alloc(&ss->css_idr, NULL, 2, 0, GFP_KERNEL);
if (err < 0)
goto err_free_percpu_ref;
css->id = err;
@ -4659,7 +4659,7 @@ static int cgroup_mkdir(struct kernfs_node *parent_kn, const char *name,
* Temporarily set the pointer to NULL, so idr_find() won't return
* a half-baked cgroup.
*/
cgrp->id = cgroup_idr_alloc(&root->cgroup_idr, NULL, 2, 0, GFP_NOWAIT);
cgrp->id = cgroup_idr_alloc(&root->cgroup_idr, NULL, 2, 0, GFP_KERNEL);
if (cgrp->id < 0) {
ret = -ENOMEM;
goto out_cancel_ref;